Hard coding refers to embedding value parameters directly in click and impression tags, instead of obtaining the data from external sources. You may want to hard code values in tags when value parameters won't change across campaigns and aren't considered dynamic (ex: site name). In some cases, Facebook Attribution will hard code site name values directly in the tags. This configuration allows for consistency across your campaigns, no matter who is implementing or generating the tags.

You may also want to hard code values in tags when third-party sources, such as publishers and ad servers, don't support macros for certain objects like campaigns, placements, and ad groups. In these cases, you can hard code specific value parameters in the tags to avoid having to create individual 1x1 tags.

The following example tags display hard coded site names ("s.a"):

https://ad.atdmt.com/i/img;adv=1234566666;ec=4444444444;c.a={campaignid};s.a=google;

https://ad.atdmt.com/i/img;adv=1234566666;ec=4444444444;c.a={campaignid};s.a=yahoo;

https://ad.atdmt.com/i/img;adv=1234566666;ec=4444444444;c.a={campaignid};s.a=criteo;

* Nguồn: Facebook